In view of the changing patterns of delivery of psychiatric services emphasizing local care and resulting in the concentration of the mentally ill in the local communities, a study is proposed which will document factors currently facilitating and hindering the social integration of these groups. The focus of the study will be to assess the level of social integration of individuals with a history of psychiatric treatment who reside in the community and to determine the most significant predictors of it in the social environment and in the type of previous hospital care they received. A probability sample of a cohort of ex-patients through California, where a large number of former psychiatric patients now reside in the community, will be taken. Two hundred and fifty structured interviews with these individuals will be completed approximately one year after their release from an inpatient psychiatric facility. A similar number of interviews will be completed with a neighbor control group. Social integration will be assessed on scales developed in our current research. In considering factors facilitating and hindering social integration important intervening variables such as level of psychological disturbance and the social desirability component in interviewee response will be controlled for in the analysis. A second major goal in the study will be to further refine and validate these social integration scales. The possibility of using the scales in a multinational study will be explored. Determining the effects of the social environment and prerelease hospital care on the level of social integration of people with a history of psychiatric treatment has important policy implications. The study will also increase our knowledge of the characteristics of this growing population group and refine and validate a viable instrument to measure the social integration of this group in local communities.